The present invention relates to the general field of monitoring a turbine engine. More specifically, it is directed to a method and system allowing automatic detection of ingestion of an object by an aircraft turbine engine during a mission.
During a mission, it is possible that foreign bodies or parts detached from the turbine engine, are ingested by the turbine engine and cause deterioration inside the latter. In particular, the impact of an object on a fan blade risks damaging the latter. In the case of deteriorations due to the ingestion of bodies foreign to the turbine engine (for example birds), one refers to FOD (<<Foreign Object Damage>>). In the case of deteriorations due to the ingestion of parts detached from the turbine engine (for example rivets, bolts, etc.), one rather refers to DOD (<<Domestic Object Damage>>).
Different known solutions exist for detecting the presence of FOD or DOD. One of these solutions is based on a measurement of the vibrations of one of the rotors of the turbine engine in order to detect the occurrence of an unbalance consecutive to the damaging of the latter by ingestion of an object. In the case of detection of unbalance, visual inspection of the turbine engine (by endoscopy for example) is carried out on the ground: the presence of impact traces, of bird feathers or of pockets on the blades at the location of the impact then allows diagnosing the presence of FOD or DOD.
Such a solution has many drawbacks. It is notably incapable of detecting the presence of FOD or DOD which do not lead to any unbalance on the rotors of the turbine engine (or to an unbalance which is too small to be detected). Moreover, endoscopic inspection of the turbine engine requires ground intervention which has to be programmed in advance and which may be tedious.
Another known solution consists of using measurement instruments loaded on-board the aircraft for detecting the presence of FOD or DOD. Thus, a turbine engine monitoring method is known from document US 2007/0250245 allowing quasi-instant detection of whether a foreign body has damaged the turbine engine. For this purpose, this method provides real-time comparison of the vibratory level of a rotor of the turbine engine with a predefined threshold. In the case of this threshold being exceeded over a predetermined period, a maintenance alert is emitted.
This method however has many disadvantages. In particular, in order that a maintenance alert be emitted, it is required that exceeding of the threshold occurs over a minimum period. There are therefore risks that certain FODs or DODs are not detected by this method.
More generally, the different known solutions for detecting FOD or DOD do not give the possibility of analyzing in real time the consequences of this ingestion on the blades of the fan.